Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
  • B01D69/12—Composite membranes; Ultra-thin membranes
  • B01D69/125—In situ manufacturing by polymerisation, polycondensation, cross-linking or chemical reaction
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
  • B01D69/02—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
  • B01D69/06—Flat membranes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
  • B01D69/08—Hollow fibre membranes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
  • B01D71/06—Organic material
  • B01D71/56—Polyamides, e.g. polyester-amides
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
  • C08G69/02—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids
  • C08G69/26—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids
  • C08G69/32—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids from aromatic diamines and aromatic dicarboxylic acids with both amino and carboxylic groups aromatically bound
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
  • C08G69/40—Polyamides containing oxygen in the form of ether groups
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2325/00—Details relating to properties of membranes
  • B01D2325/02—Details relating to pores or porosity of the membranes
  • B01D2325/022—Asymmetric membranes

Definitions

• the invention relates to a process for the preparation of polyether amide solutions, the use of these solutions, dialysis membranes made from polyether amide, which may optionally contain further polymers as blend components, and their production from polyether amide solutions.
• the invention relates to a process for the preparation of polyether amide solutions, in which one or more dicarboxylic acid derivatives of the general formula I wherein Ar denotes a divalent, aromatic or heteroaromatic radical, the two carbonyl groups on non-adjacent ring carbon atoms, ie not in the ortho position to one another, and the Ar radical optionally with one or two branched or unbranched radicals from the group of the C 1 - C 3 alkyl, C 1 -C 3 alkoxy, aryl, aryloxy, C 1 -C 6 perfluoroalkyl, C 1 -C 6 perfluoroalkoxy, fluorine, chlorine, bromine and / or iodine, with one or more aromatic diamines of the general formula II wherein X for a group -C (CH 3 ) 2 -, -C (CF 3 ) 2 , -CO-, -SO-, -SO 2 -, -CH 2
• membranes are widely used in blood treatment procedures such as hemodialysis or plasmaphoresis.
• a large number of membrane materials are used, as described in: E. Wetzels, A. Colombi, P. Dittrich, HJ Gurland, M. Kessel, H. Klinkmann in Hemodialysis, peritoneal dialysis, membrane plasmaphoresis and related processes ", Springer Verlag, 3rd edition (1986).
• the membrane materials can be divided into membranes made on the one hand from synthetic polymers and on the other hand made of cellulosic polymers, such as e.g. Cuprophan.
• the membranes are used both in hollow fiber modules and in flat membrane configurations.
• Membranes made of synthetic polymers have an improved blood tolerance compared to membranes made from cellulosic materials, e.g. lower complement activation discussed.
• Sterilization with ethylene oxide is predominantly used as the sterilization method in synthetic membranes today.
• steam sterilization (20 min. At 121 ° C with saturated water vapor) or sterilization at elevated temperature is used (see KH Wallophußer, Practice of Sterilization, Disinfection, Preservation ", 3rd edition, Thieme Verlag, 1981).
• DE 3936785 describes the sterilization of polysulfone membranes with hot water.
• Dialysis membranes made of synthetic polymers often consist of another structure-forming and stabilizing polymer component, hydrophilic component and are constructed in the form of a blend or as a copolymer.
• hydrophilic components are polyvinyl pyrrolidone (PVP) or polyethylene glycol (PEG).
• PVP polyvinyl pyrrolidone
• PEG polyethylene glycol
• polyamide membranes occupy an outstanding position in dialysis, hemodiafiltration and hemofiltration. This is due to their good performance and blood tolerance (see in Polyamides - The Evolution of a Synthetic Membrane for Renal Therapy ", ed. By S. Shaldon, KM Koch, contribution to Nephrology No. 96, Karger Verlag 1992).
• D1 describes the advantages of asymmetric porous membranes made from aromatic polyetheramides or polyaramides over other membrane materials such as cellulose or polyether sulfone. If solutions of polyetheramides are added before the phase inversion, hydrophilic polymers which mix homogeneously with the polyaramides, such as, for example, polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG), membranes with high hydrophilicity can be obtained (D2).
• PVP polyvinylpyrrolidone
• PEG polyethylene glycol
• polyetheramide solutions which are obtained directly by reaction of the corresponding monomers in the solvent suitable for membrane production, is technically particularly advantageous for the membrane preparation.
• the complex isolation of the polymer can be omitted.
• D1 discloses the reaction of aromatic diacid chlorides with aromatic diamines to form polyaramides or polyetheramides in polar aprotic solvents such as N-methylpyrrolidone or dimethylacetamide.
• salt such as e.g. Calcium chloride added.
• hydrochloric acid is released, which is only loosely bound to the basic solvent and, without subsequent neutralization, leads to severe corrosion of system parts and to the hydrolysis of the polyaramide formed.
• the D3 proposes the use of an inorganic solubility improver in salt form.
• Halides, nitrates, sulfates and / or perchlorates of the alkali or alkaline earth metals, preferably LiCl, are listed in the D3.
• saline polyaramide solutions available according to the prior art are used for the production of membranes by the phase inversion process, then after the polyaramide solutions have been coagulated in a non-solvent, such as e.g. Water, the salts are washed out of the membrane.
• a non-solvent such as e.g. Water
• the salts are washed out of the membrane. This process is associated with considerable effort, especially if the lowest possible salt content of the finished membrane is to be aimed for in applications in the medical field, for example when used as a dialysis membrane.
• salt-free polyether amide solutions can be obtained by redissolving precipitated, washed and dried poly (ether) amide powder. This process is expensive and generally involves the consumption of substantial amounts of rinse solvent and wash water.
• Another object of the invention was to provide storage-stable solutions of polyaramides or polyetheramides from which membranes can be manufactured.
• Another object of the invention is a steam-sterilizable dialysis membrane with good blood tolerance and high selectivity.
• Another object of the invention is to provide a method for producing steam-sterilizable dialysis membrane with good blood tolerance and high selectivity.
• the hydrochloric acid is neutralized to ammonium chloride, which is almost insoluble in the polar aprotic solvents such as N-methylpyrrolidone or N, N-dimethylacetamide and can be removed by simple filtration.
• polar aprotic solvents such as N-methylpyrrolidone or N, N-dimethylacetamide
• solubility of ammonium chloride is well below 0.1%, so that this salt can be largely removed by simple filtration.
• the polyaramide solutions according to the invention can be obtained in high concentrations in the desired solvents without any addition of salt, and a two-stage neutralization with formation of soluble salts is superfluous.
• terephthalic acid dichloride and / or isophthalic acid dichloride are used as compounds of the formula I.
• Preferred substances of the general formula II include 2,2'-bis [4- (4'-aminophenoxy) phenyl] propane, Bis [3- (3'-aminophenoxy) phenyl] sulfone, Bis [4- (4'-aminophenoxy) phenyl] sulfone, Bis [4- (4'-aminophenoxy) phenyl] methane and / or 2,2'-bis [4- (4'-aminophenoxy) phenyl] hexafluoropropane.
• aromatic diamines of type II can be replaced by m-phenylenediamine.
• Polymer solutions are very particularly preferably prepared as polycondensates from terephthalic acid dichloride and isophthalic acid dichloride as dicarboxylic acid dichlorides and 2,2'-bis [4- (4'-aminophenoxy) phenyl] propane as amine component, furthermore preferably a proportion of less than 50 mol% of the amine component is replaced by m-phenylenediamine.
• the solution condensation of aromatic dicarboxylic acid dichlorides of the formula I with aromatic diamines of the formula II and optionally m-phenylenediamine and / or diamines of the formula III is carried out in aprotic polar solvents, preferably of the amide type.
• Solvents N-methyl-2-pyrrolidone (NMP) or N, N-dimethylacetamide or mixtures thereof are particularly favorable.
• the polycondensation temperatures are usually between -20 ° C and + 120 ° C, preferably between + 10 ° C and + 100 ° C. Particularly good results are achieved at reaction temperatures between + 10 ° C and + 80 ° C.
• the polycondensation reactions are preferably carried out in this way and the amount of the monomers to be polycondensed is selected such that, after the reaction has ended, the concentration of the polymer in the solution is between 3 and 50% by weight. Between 5 and 35% by weight of polycondensate is preferably present in the solution.
• the polycondensation can be carried out in a conventional manner, e.g. B. be stopped by adding monofunctional compounds such as benzoyl chloride. After the end of the polycondensation, ie when the polymer solution for If the Staudinger index required for further processing has been reached, the hydrogen chloride formed which is bound to the amide solvent is neutralized by introducing ammonia. After neutralization, the solutions are filtered and, if necessary, degassed and are thus stable in storage for several weeks without changing their properties which are important with regard to membrane production. The concentration of the solutions and the molecular weight of the polymer (Staudinger index) remain essentially unchanged as important factors influencing membrane properties such as porosity, mechanical stability, permeability and retention capacity.
• monofunctional compounds such as benzoyl chloride
• the polyetheramides produced according to the invention ensure, particularly surprisingly, the availability of highly concentrated solutions without the addition of salt. Concentrations of e.g. 24% in polar aprotic solvents such as N-methylpyrrolidone or dimethylacetamide are easily possible.
• the polyetheramides obtained according to the process of the invention have a Staudinger index of 0.5 to 5 dl / g (measured in N-methylpyrrolidone with the addition of 0.05% LiBr), preferably between 0.8 and 2.0 dl / g. In contrast to other known processes (melt process for the production of polyetheramides), the preferred range is easily reached.
• the higher molecular weights (corresponding to higher Staudinger indices (> about 0.8 dl / g)) particularly favor film-forming processes for the production of membranes. In such an application, the higher molecular weight leads to a higher processing (spinning) speed.
• the salt-free solutions of polyaramides according to the invention have a significantly lower viscosity compared to solutions of the same concentration which contain stoichiometric amounts of salt, such as calcium chloride, as used in the neutralization of the Polycondensation solutions can be obtained, for example, with calcium oxide (Example 2).
• the low viscosity has great advantages for the production of hollow fiber membranes, since even higher polymer concentrations can still be processed without problems and therefore shorter filtration times for the solutions and higher spinning speeds can be achieved in technical hollow fiber production. (Table 5)
• the solutions obtained can be processed particularly advantageously after filtration without isolating the polymer.
• the polyether amide solutions produced in the invention are particularly well suited for the production of semipermeable, porous, asymmetrical membranes.
• the use for the production of flat membranes is favorable.
• the production of hollow fiber membranes is very particularly preferred.
• the invention accordingly also relates to a membrane which is composed of a polyamide, is polyether amide, which has the required temperature stability and at the same time has the good blood tolerance properties of polyamide.
• it is a semipermeable, porous, asymmetrical membrane comprising a polyaramide, containing one or more structural units of the general formula I 'as recurring structural units wherein Ar denotes a divalent, aromatic or heteroaromatic radical, the two carbonyl groups on non-adjacent ring carbon atoms, ie not in the ortho position to one another, and the Ar radical optionally with one or two branched or unbranched Radicals from the group consisting of C 1 -C 3 alkyl, C 1 -C 3 alkoxy, aryl, aryloxy, C 1 -C 6 perfluoroalkyl, C 1 -C 6 perfluoroalkoxy, fluorine, chlorine, Bromine and / or iodine is substituted, and based on the sum
• the membrane according to the invention is characterized in that it is arranged on a carrier layer made of plastic fleece which is permeable to flowable media or on a fabric.
• the membrane of the invention is preferably designed as a hollow fiber membrane.
• N-methylpyrrolidone or dimethylacetamide usually used in the production of the polyaramides are also particularly preferably used for the production of membranes. This means that the polymer, which is laboriously isolated from NMP or DMAc, is then redissolved in precisely this solvent. This does not apply when using solutions according to the invention.
• the invention therefore also includes a method for producing a semipermeable, porous, asymmetric membrane, in which a solution containing a polymer of at least one polyaramide containing as repeating structural units one or more structural units of the general formula I ' wherein Ar denotes a divalent, aromatic or heteroaromatic radical, the two carbonyl groups on non-adjacent ring carbon atoms, ie not in the ortho position to one another, and the Ar radical optionally with one or two branched or unbranched radicals from the group of the C 1 - C 3 alkyl, C 1 -C 3 alkoxy, aryl, aryloxy, C 1 -C 6 perfluoroalkyl, C 1 -C 6 perfluoroalkoxy, fluorine, chlorine, bromine and / or iodine, and based on the sum of (II ') and (III') to 50 to 100 mol% of structural units of the formula (II ') wherein X for
• customary additives such as PEG or PVP are added to the polymer solution.
• the solution resulting from the polycondensation is used without isolation of the polymer for membrane production by the phase inversion process.
• phase inversion technology is a membrane made of a polymer solution consisting of solvent such as N-methylpyrrolidone (NMP) or dimethylacetamide (DMAc) or mixtures thereof, of the polyether amide and furthermore of hydrophilic components such as PVP or PEG
• solvent such as N-methylpyrrolidone (NMP) or dimethylacetamide (DMAc) or mixtures thereof
• NMP N-methylpyrrolidone
• DMAc dimethylacetamide
• PVP or PEG polyether amide
• All solvents that are completely miscible with the solvent (NMP or DMAc) can be used as non-solvents
• water, monohydric or polyhydric alcohols, organic solvents such as acetone or mixtures of these solvents with one another or with the solvent preferably water or a mixture of water and NMP or DMAc together with PVP or PEG, through a targeted combination of polyether amide, more hydrophilic Component and non-solvent system and
• the concentration of polyether amide in the spinning solution is 5-25% by weight for the molecular weights indicated above and for the hydrophilic ones Component 0 to 20% by weight.
• the non-solvent system is composed of water with 0 to 60% by weight: solvent and 0 to 10% hydrophilic component.
• Asymmetric membranes are produced as described in EPA 0 305 787 A1.
• the first layer on the blood-contacting hollow fiber side consists of a very thin skin, on which the separation takes place according to the molecular size. The result of this is that the separation takes place on the surface and not within the membrane, so that no proteins can penetrate into the membrane.
• the second intermediate layer consists of an approx. 10 mm thick porous sponge structure, which stabilizes the first layer and is characterized by a minimal diffusive and convective flow resistance.
• the third layer which covers 80% of the membrane thickness, provides high mechanical stability and, thanks to minimal convective and diffusive resistance with a large-pore outer surface, enables the separated molecules to be quickly transported into the dialysate circuit.
• Dialysis membranes produced in this way have a chemical and thermal stability which is sufficient for carrying out steam sterilization (121 ° C., 20 min) and show membrane performance data which are in the range of good high-flux dialysis membranes.
• the diamines are dissolved in N-methylpyrrolidone in the amounts given in Table 1 at 20.degree.
• the corresponding amounts of terephthalic acid or isophthalic acid dichloride are metered in as quickly as possible to this solution.
• a spontaneous increase in temperature to 40-60 ° C. and an increase in viscosity are observed.
• the amino end groups still present are sealed by adding stoichiometric amounts of benzoyl chloride. It is left for 15 min. then react and neutralize the HCl formed by introducing gaseous ammonia at temperatures between 40 and 110 ° C.
• the viscosity of a 19.7% solution of polymer 1 with a Staudinger index of 1.15 dl / g in N-methylpyrrolidone is 79,000 m ⁇ Pa ⁇ s at 25 ° C.
• an analog solution which contains an amount of calcium chloride (4.1%), which is obtained by stoichiometric neutralization with calcium oxide has a viscosity of 112,000 m ⁇ Pa ⁇ s.
• the properties of the membranes are in the range of good high-flux dialysis membranes.
• Example 3.1 Membrane made of polymer 1
• the concentrations of polyether amide and PVP used can be found in column 1 in table 2. Water was used as the non-solvent system. Table 2 shows in particular the performance data of steam sterilized membranes.
• Example 3.2 Membrane made of polymer 2
• Example 3.2 polymer 2 (Table 1, Example 1) was used.
• the steam-sterilized membrane is a polyether amide membrane composed of a polycondensate of terephthalic acid dichloride / isophthalic acid dichloride in a molar ratio of 8: 2 as the acid component and 2,2'-bis [4- (4'-aminophenoxy) phenyl] -propane / m-phenylenediamine in a molar ratio of 5: 5 as the diamine component.
• the concentrations of polyether amide and PVP used can be found in column 1 in table 3.
• the nonsolvent system consisted of 70% water and 30% NMP.
• Table 3 contains the spinning parameters used and the determined performance data of the membrane obtained.
• Example 3.3 Membrane made of polymer 3
• Example 3.3 polymer 3 (Example 1, Table 1) was used.
• the steam-sterilized membrane is a polyether amide membrane made from a polycondensate of terephthalic acid dichloride / isophthalic acid dichloride in a molar ratio of 8: 2 as the acid component and 2,2'-bis [4- (4'-aminophenoxy) phenyl] propane / m-phenylenediamine in a molar ratio of 7: 3 as the diamine component.
• the concentrations of polyether amide and PVP used can be found as the composition of the spinning solution in column 1 in table 4. Water was used as the non-solvent system. Table 4 contains the determined performance data of the membrane obtained.
• Example 5 complement activation and cytotoxicity were investigated using polymer 1.
• polyetheramide from ⁇ 8: 2 (terephthalic acid dichloride / isophthalic acid dichloride) ⁇ and 2,2'-bis [4- (4'-aminophenoxy) phenyl] propane the blood tolerance by means of complement activation is compared as a TCC value in Table 6 to other common dialysis membranes quantified.
• the polyether amide is at the same level as the well-rated poly amide membrane.
• the cytotoxicity was determined by determining the inhibition according to the ICG test SF / 6TI-014. No inhibition of cell growth was found.

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• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Separation Using Semi-Permeable Membranes (AREA)
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• 1995
  • 1995-12-28 DE DE19549001A patent/DE19549001A1/de not_active Withdrawn
• 1996
  • 1996-12-17 EP EP96120248A patent/EP0781593A3/fr not_active Withdrawn
  • 1996-12-20 US US08/771,230 patent/US5859175A/en not_active Expired - Fee Related
  • 1996-12-27 JP JP8350031A patent/JPH09194590A/ja active Pending

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